steinway



2 Sheets--Sheet I.

C. F. T. STBINWAY. Key Frame Bed for Piano Fortes.

(N'o Model.)

Patented Oct. 5, 1880.

NAPETERS, PH HOGRAPHER. WASHINGTON, u C;

(No Model.) Sheets--Sheet 2.

C. F. T. STBIN'WAY. Key Frame Bed for Piano Fortes.

No. 232,857. Patented Oct. 5,1880.

UNITED STATES PATENT OEEICE.

C. F. THEODOR STEINWAY, OF NEW YORK, N. Y.

KEY-FRAME BED FOR` PIANO-FORTES.

SPECIFICATION forming part of Letters Patent No. 232,857', dated October 5, 1880.

' Application tiled May 13,1880. (No model.)

To all whom it 'may concern:

Be it known that I, (l. F. THEoDoE STEIN- WAY, of the city and State of New York, have invented certain Improvements in Key- Board or Key-Frame Beds for Piano-Fortes, of which the following is a specification.

My improvements relate to the construction of the wooden bed which supports the keyframe in a piano-forte, and are designed to prevent the bed from acting asa soundingboard in augmenting the sound or thud made by the key-levers in striking against the touchrail of the key-frame, and also to prevent the warping of the bed and consequent upheaval of any part of the key-frame; and my invention consists in a key-frame bed composed of parallel strips of wood and end cleats, in which the parallel strips are secured by ton gued and grooved joints, the vertical joints between the parallel strips being filled with a soft packing, preferably of fibrous material, for the purpose of obstructing thelateral transmission of vibrations from one strip to another.

The accompanying drawings are as follows:

Figure lis a top view of my key-frame bed. Fig. 2 is a side elevation of one ot the strips, showing the cleats in section through theline x x on Fig. l; and Fig. 3 is a transverse section through the line y y on Fig. l. Fig. 4 is an isometrical perspective of a portion of the case of an upright piano-forte, showing a few of the keys, a part of the key-frame, and a portion of my improved key-frame bed fastened in the usual manner to the projecting arms of the case.

Referring to the drawings, it will be seen that the bed is composed of a number of narrow wooden strips, A, which are secured at their ends respectively to the cleats B B by tong`ued and grooved joints b b. The strips A are also tongued and grooved to each other 5 but the opposed vertical planes of their ton gued and grooved joints a are slightly' separated, and are prevented from direct contact with each other by the interposition between them of the soft packing C, preferably Vof fibrous material.

In the drawings the fibrous packing C is represented as being interposed between the bottom of the groove of each strip and the face of the tongue of the adjoining strip.

The packing may be introduced into the joints ct either above or below the tongues; or, if desired, between all the opposed vertical faces of the joint, the effect of such interposition being that vibrations set up in one of the strips are not readily communicated to the adjoining strip.

It will, of course, be understood that the packing may be composed ot' any material incapable of acquiring and transmitting sonorous vibrations.

The key-board beds heretofore employed are of such width that they are liable, by their warping, to cause an upheaval of a portion. of the key-frame and a consequent derangement ot the action.

By the use of the narrow strips A all danger ot' warping is avoided, and the strips themselves, by reason of their small area in crosssection, are capable of being more easily and eifectually seasoned than the wider stuff herctofore used for the panels of beds.

My improved key-frame bed, which may be applied with equal advantage to both horizontal and upright pianos, is secured to the case ot' the piano in the same way that the ordinary key-board bed is secured.

In au upright piano-forte, as shown in Fig. 4, the end cleats, B B, are respectively fastened yto the under sides of the arms D, projecting from the front of the case E.

The keys F are arranged upon the usual key-frame G.

In Fig. 4 of the drawings a portion of the key-frame is broken away to more clearly exhibit my improved key-frame bed and its relation to the keys.

When the key is depressed the front end, f, of the key-lever strikes against the usual cushion upon the touch-rail g, and makes a noise which, when the ordinary key-board bed is employed, is like the sound of a drum, this noise being made more perceptible because the ordinary key-frame bed or key-board acts as a sounding-board and unplcasantly augments it. By my invention this unpleasant augmentation of the noise of the key is prevented.

I claim as my invention- 1. The combination, in a piano-forte, of the keys and key-frame with a key-frame bed com- IOO at their ends respectively to the cleats B B, and tongued and grooved to each other, and having interposed between theirV adjoining edges the packing G, substantially as and for the purposes described.

C. F. THEODOR STEINWAY.

Witnesses:

M. L. ADAMS, EDWD. PAYsoN. 

